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Efficient spread space-time block coding scheme in multiple antenna systems
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作者 Qiu Ling Zheng Xiayu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期258-262,共5页
Space-time coding is an important technique that can improve transmission performance at fading environments in mobile communication systems. In this paper, we propose a novel diversity scheme using spread spacetime b... Space-time coding is an important technique that can improve transmission performance at fading environments in mobile communication systems. In this paper, we propose a novel diversity scheme using spread spacetime block coding (SSTBC) in multiple antenna systems. At the transmitter, the primitive data are serial to parallel converted to multiple data streams, and each stream is rotated in constellation. Then Walsh codes are used to spread each symbol to all antenna space in a space-time block. The signals received from all receiver antennas are combined with the maximum ratio combining (MRC), equalized with linear equalizer to eliminate the inter-code interference and finally demodulated to recover to transmit data by using the one-symbol maximum likelihood detector. The proposed scheme does not sacrifice the spectrum efficiency meanwhile maintains the transceiver with low complexity. Owing to the transmission symbols of different transmit antennas passing through all the spatial subchannels between transceiver antenna pairs, the system obtains the partial additional space diversity gain of all spatial paths. It is also shown that the diversity gain is better than the previous space-time block coding (STBC) schemes with full transmission rate. 展开更多
关键词 multiple antennas spread space-time block coding (SSTBC) DIVERSITY full transmission rate.
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A New Generalized Complex Orthogonal Space-Time Block Codes
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作者 单红梅 胡光锐 《Journal of Shanghai University(English Edition)》 CAS 2005年第3期241-243,共3页
Recent research challenges in the wireless communication include the usage of diversity and efficient coding to improve data transmission quality and spectral efficiency. Space diversity uses multiple transmitting and... Recent research challenges in the wireless communication include the usage of diversity and efficient coding to improve data transmission quality and spectral efficiency. Space diversity uses multiple transmitting and/or receiving antennas to create independent fading channels without penalty in bandwidth efficiency. Space-time block coding is an encoding scheme for communication over Rayleigh fading channels using multiple transmitting antennas. Space-time block codes from complex orthogonal designs exist only for two transmitting antennas. This paper generalizes a new complex orthogonal space-time block code for four transmitting antennas, whose decoding complexity is very low. Simulations show that the generalized complex orthogonal space-time block code has low bit error rate, full rate and possibly large diversity. 展开更多
关键词 space diversity space-time block code multiple antennas generalized complex orthogonal designs.
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CLOSED-FORM SPACE-TIME CHANNEL BLIND ESTIMATION FOR SPACE-TIME CODED MC-CDMA SYTEMS WITH UNIFORM LINEAR ARRAY
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作者 Zeng Yanxing Yin Qinye Luo Ming Zhang Jianguo 《Journal of Electronics(China)》 2006年第3期321-327,共7页
This paper proposes a closed-form joint space-time channel and Direction Of Arrival (DOA) blind estimation algorithm for space-thne coded Multi-Carrier Code Division Multiple Access (MC-CDMA) systems equipped with... This paper proposes a closed-form joint space-time channel and Direction Of Arrival (DOA) blind estimation algorithm for space-thne coded Multi-Carrier Code Division Multiple Access (MC-CDMA) systems equipped with a Uniform Linear Array (ULA) at the base station in frequency-selective fading environments. The algorithm uses an ESPRIT-like method to separate multiple co-channel users with different impinging DOAs. As a result, the DOAs for multiple users are obtained. In particular, a set of signal subspaces, every one of which is spanned by the space-time vector channels of an individual user, are also obtained. From these signal subspaces, the space-time channels of multiple users are estimated using the subspace method. Computer simulations illustrate both the validity and the overall performance of the proposed scheme. 展开更多
关键词 Multi-Carrier code Division multiple space-time channel Antenna array Direction Of Arrival Access (MC-CDMA) space-time Coding (STC) (DOA)
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MULTIPLE TRELLIS CODED ORTHOGONAL TRANSMIT SCHEME FOR MULTIPLE ANTENNA SYSTEMS
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作者 Lv Shujuan Wei Guo Zhu Jinkang 《Journal of Electronics(China)》 2006年第3期355-360,共6页
In this paper, a novel multiple trellis coded orthogonal transmit scheme is proposed to exploit transmit diversity in fading channels. In this scheme, a unique vector from a set of orthogonal vectors is assigned to ea... In this paper, a novel multiple trellis coded orthogonal transmit scheme is proposed to exploit transmit diversity in fading channels. In this scheme, a unique vector from a set of orthogonal vectors is assigned to each transmit antenna. Each of the output symbols from the multiple trellis encoder is multiplied with one of these orthogonal vectors and transmitted from corresponding transmit antennas. By correlating with corresponding orthogonal vectors, the receiver separates symbols transmitted from different transmit antennas. This scheme can be adopted in coherent/differential systems with any number of transmit antennas. It is shown that the proposed scheme encompasses the conventional trellis coded unitary space-time modulation based on the optimal cyclic group codes as a special case. We also propose two better designs over the conventional trellis coded unitary space-time modulation. The first design uses 8 Phase Shift Keying (8-PSK) constellations instead of 16 Phase Shift Keying (16-PSK) constellations in the conventional trellis coded unitary space-time modulation. As a result, the product distance of this new design is much larger than that of the conventional trellis coded unitary space-time modulation. The second design introduces constellations with multiple levels of amplitudes into the design of the multiple trellis coded orthogonal transmit scheme. For both designs, simulations show that multiple trellis coded orthogonal transmit schemes can achieve better performance than the conventional trellis coded unitarv space-time schemes. 展开更多
关键词 space-time Trellis code Modulation (TCM) multiple TCM (MTCM) DIFFERENTIAL UNITARY
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UNIT-RATE COMPLEX ORTHOGONAL SPACE-TIME BLOCK CODE CONCATENATED WITH TURBO CODING
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作者 Yu Xiangbin Bi Guangguo 《Journal of Electronics(China)》 2006年第3期346-349,共4页
Space-Time Block (STB) code has been an effective transmit diversity technique for combating fading due to its orthogonal design, simple decoding and high diversity gains. In this paper, a unit-rate complex orthogonal... Space-Time Block (STB) code has been an effective transmit diversity technique for combating fading due to its orthogonal design, simple decoding and high diversity gains. In this paper, a unit-rate complex orthogonal STB code for multiple antennas in Time Division Duplex (TDD) mode is proposed. Meanwhile, Turbo Coding (TC) is employed to improve the performance of proposed STB code further by utilizing its good ability to combat the burst error of fading channel. Compared with full-diversity multiple antennas STB codes, the proposed code can implement unit rate and partial diversity; and it has much smaller computational complexity under the same system throughput. Moreover, the application of TC can effectively make up for the performance loss due to partial diversity. Simulation results show that on the condition of same system throughput and concatenation of TC, the proposed code has lower Bit Error Rate (BER) than those full-diversity codes. 展开更多
关键词 space-time Block (STB) codes Turbo-Coding (TC) Unit-rate multiple antennas Transmit diversity
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Performance of Block Space-Time Code in Wireless Channel Dynamics
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作者 Won Mee JANG Jong Hak JUNG 《International Journal of Communications, Network and System Sciences》 2009年第6期461-468,共8页
In this work, we observe the behavior of block space-time code in wireless channel dynamics. The block space-time code is optimally constructed in slow fading. The block code in quasistatic fading channels provides af... In this work, we observe the behavior of block space-time code in wireless channel dynamics. The block space-time code is optimally constructed in slow fading. The block code in quasistatic fading channels provides affordable complexity in design and construction. Our results show that the performance of the block space-time code may not be as good as conventionally convolutional coding with serial transmission for some channel features. As channel approaches fast fading, a coded single antenna scheme can collect as much diversity as desired by correctly choosing the free distance of code. The results also point to the need for robust space-time code in dynamic wireless fading channels. We expect that self-encoded spread spec-trum with block space-time code will provide a robust performance in dynamic wireless fading channels. 展开更多
关键词 space-time codes DIVERSITY multiple Transmit ANTENNAS Self-Encoded SPREAD SPECTRUM
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Improved scheme with cooperative diversity based on distributed space-time block coding
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作者 Du Na Xu Dazhuan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期463-469,共7页
An improved scheme with cooperative diversity based on distributed space-time block coding (WCD- DSTBC) is proposed, which effectively achieves diversity gains and improves the performance of the system by sharing s... An improved scheme with cooperative diversity based on distributed space-time block coding (WCD- DSTBC) is proposed, which effectively achieves diversity gains and improves the performance of the system by sharing some single-antenna users' antennas to form a virtual antenna array and combining with distributed spacetime block coding (DSTBC) mode. Then the relation between the system BER and the interuser BER for WCDDSTBC scheme is theoretically derived and the closed-form expression of BER for WCD-DSTBC system is obtained. The simulation results show that the proposed WCD-DSTBC scheme achieves distinct gains over the non-cooperative multi-carrier CDMA (MC-CDMA) system. When system BER is le-3 and interuser BER is le-3, about 2.5 dB gain can be gotten. When interuser channel state information (CSI) outgoes the users' individual CSI, about 3 dB gain is also achieved. 展开更多
关键词 multiple input multiple output cooperative diversity distributed space-time block coding multicarrier CDMA.
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A NOVEL LINEAR DIFFERENTIAL SPACE-TIME MODULATION
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作者 Wang Lei Zhu Shihua Wang Jun 《Journal of Electronics(China)》 2007年第5期593-599,共7页
Based on the Complex Orthogonal Linear Dispersion (COLD) code,a novel linear Differ- ential Space-Time Modulation (DSTM) design is proposed in this paper.Compared with the existing nonlinear DSTM schemes based on grou... Based on the Complex Orthogonal Linear Dispersion (COLD) code,a novel linear Differ- ential Space-Time Modulation (DSTM) design is proposed in this paper.Compared with the existing nonlinear DSTM schemes based on group codes,the proposed linear DSTM scheme is easier to design, enjoys full diversity and allows for a simplified differential receiver,which can detect the transmitted symbols separately.Furthermore,compared with the existing linear DSTM based on orthogonal design, our new construction can be applied to any number of transmit antennas.Similar to other algorithms, the proposed scheme also can be demodulated with or without channel estimates at the receiver,but the performance degrades approximately by 3dB when estimates are not available. 展开更多
关键词 multiple antennas Transmit diversity space-time coding Differential modulation Wireless communications
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SIMPLE AND EFFICIENT SPACE-TIME CHANNEL AND DOA ESTIMATION TECHNIQUES IN TD-SCDMA SYSTEMS
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作者 Li Ping'an Ma Ning 《Journal of Electronics(China)》 2006年第5期671-674,共4页
In this paper, a simple method is presented for multi-user space-time channel estimation in Time Division-Synchronized Code Division Multiple Access (TD-SCDMA) systems. The method is based on a spe- cific midamble ass... In this paper, a simple method is presented for multi-user space-time channel estimation in Time Division-Synchronized Code Division Multiple Access (TD-SCDMA) systems. The method is based on a spe- cific midamble assignment strategy, which results in a cyclic Toeplitz midamble-matrix in the linear equation of the received data vectors. A Fast Fourier Transform (FFT)-based algorithm is used to obtain the estimate of the uplink multi-user space-time channels. Furthermore, the estimated space-time channel is applied to the identification of multi-paths for each user, and Direction Of Arrival (DOA) estimation for each path is carried out by using the extracted spatial signature vector. Aside from the simplicity in computation, the proposed di- rection of arrival estimation method can effectively resolve multi-paths regardless of the correlation and angle separations of the multi-paths. 展开更多
关键词 Time Division-Synchronized code Division multiple Access (TD-SCDMA) space-time channel estimation Direction Of Arrival (DOA) estimation
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Performance of STBC-MC-CDMA system based on complex wavelet packet and turbo coding
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作者 虞湘宾 毕光国 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期398-404,共7页
On the basis of analyzing the principle of the space-time coding technique and the multi-carrier code division multiple access (MC-CDMA) technique, adopting the turbo codes as channel coding and the optimized comple... On the basis of analyzing the principle of the space-time coding technique and the multi-carrier code division multiple access (MC-CDMA) technique, adopting the turbo codes as channel coding and the optimized complex wavelet packet as multi-carrier modulation, a novel space-time block coded the MC-CDMA system based on complex wavelet packet and turbo coding is proposed, and the system bit error rate (BER) performance in the Rayleigh fading channel is investigated. The system can make full use of space-time block codes' transmit diversity and turbo codes' good ability against fading channel to improve the BER performance significantly, and it can also avoid the decrease of spectrum efficiency of conventional MC-CDMA due to inserting cyclic prefix (CP) by utilizing superior characteristics of the optimized complex wavelet packet. Simulation results show that the proposed space-time block coded MC-CDMA system based on the complex wavelet packet performs better than the conventional space-time block coded MC-CDMA (STBC-MC-CDMA) system, and slightly outperforms the STBC-MC-CDMA with CP. Moreover, the application of the space-time block coding technique concatenated with turbo codes strengthens the system ability to combat various interferences in fading channel further. 展开更多
关键词 multi-carrier technique complex wavelet packet space-time block code code division multiple access turbo coding
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Multi-dimensional blind separation method for STBC systems 被引量:3
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作者 Minggang Luo Liping Li +1 位作者 Guobing Qian Huaguo Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第6期912-918,共7页
Intercepted signal blind separation is a research topic with high importance for both military and civilian communication systems. A blind separation method for space-time block code (STBC) systems is proposed by us... Intercepted signal blind separation is a research topic with high importance for both military and civilian communication systems. A blind separation method for space-time block code (STBC) systems is proposed by using the ordinary independent component analysis (ICA). This method cannot work when specific complex modulations are employed since the assumption of mutual independence cannot be satisfied. The analysis shows that source signals, which are group-wise independent and use multi-dimensional ICA (MICA) instead of ordinary ICA, can be applied in this case. Utilizing the block-diagonal structure of the cumulant matrices, the JADE algorithm is generalized to the multidimensional case to separate the received data into mutually independent groups. Compared with ordinary ICA algorithms, the proposed method does not introduce additional ambiguities. Simulations show that the proposed method overcomes the drawback and achieves a better performance without utilizing coding information than channel estimation based algorithms. 展开更多
关键词 multiple input multiple output (MIMO) space-time block code (STBC) multi-dimensional independent component analysis (MICA) blind separation
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Performance of multiuser CDMA system with space-time block coding in MIMO Rayleigh fading channels 被引量:3
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作者 YU XiangBin DONG Tao BI GuangGuo 《Science in China(Series F)》 2009年第12期2296-2307,共12页
In this paper, by introducing orthogonal space-time coding scheme, the multiuser CDMA systems with different space time codes are given, and corresponding system performance is investigated over Rayleigh fading channe... In this paper, by introducing orthogonal space-time coding scheme, the multiuser CDMA systems with different space time codes are given, and corresponding system performance is investigated over Rayleigh fading channel. A low-complexity multiuser receiver scheme is developed for space-time coded CDMA systems. The scheme can make full use of the complex orthogonality of space-time coding to simplify the high decoding complexity of the existing scheme. Compared to the existing scheme with exponential decoding complexity, it has linear decoding complexity. Based on the performance analysis and mathematical calculation, average bit error rate (BER) of the system is derived in detail, and tight closed-form approximation expressions of BER are attained. Simulation results on average BER are in agreement with the theory analysis. The results show that the proposed scheme can achieve almost the same performance as the existing scheme. Moreover, on the condition of same system throughput and concatenation of channel code, the given full-rate space-time coded CDMA system has lower BER than the full-diversity space-time coded CDMA systems. 展开更多
关键词 space-time block coding code division multiple access (CDMA) full diversity full rate multiple input multiple output (MIMO)
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A HIGH RESOLUTION WIDE SWATH SAR METHOD BASED ON INTRA-PULSE NULL STEERING AND MIMO 被引量:1
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作者 Chen Longyong Liang Xingdong Ding Chibiao 《Journal of Electronics(China)》 2008年第6期813-816,共4页
High Resolution Wide Swath (HRWS) Synthetic Aperture Radar (SAR) often suffers from low Signal-to-Noise Ratio (SNR) due to small transmitting antenna, especially in phased array antenna systems. Digital Beam Forming (... High Resolution Wide Swath (HRWS) Synthetic Aperture Radar (SAR) often suffers from low Signal-to-Noise Ratio (SNR) due to small transmitting antenna, especially in phased array antenna systems. Digital Beam Forming (DBF) based on Single Input and Multiple Output (SIMO) achieves receiving array gain at the cost of increasing data rate. This letter proposes a new HRWS SAR method, which employs intra-pulse null steering to get receiving gain in elevation and decrease the data rate, and Multiple Input and Multiple Output (MIMO) using Space-Time Block Coding (STBC) in azimuth to get transmitting gain and receiving array gain simultaneously. The feasibility is verified by deduction and simulations. 展开更多
关键词 High Resolution Wide Swath (HRWS) Synthetic Aperture Radar (SAR) Intra-pulse null steering multiple Input and multiple Output (MIMO) Signal-to-Noise Ratio (SNR) space-time Block Coding (STBC)
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An MMSE Decoding Algorithm without Matrix Inversion in QSTBC 被引量:1
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作者 刘于 何子述 《Journal of Electronic Science and Technology of China》 2005年第4期325-327,共3页
The matrix inversion operation is needed in the MMSE decoding algorithm of orthogonal space-time block coding (OSTBC) proposed by Papadias and Foschini. In this paper, an minimum mean square error (MMSE) decoding ... The matrix inversion operation is needed in the MMSE decoding algorithm of orthogonal space-time block coding (OSTBC) proposed by Papadias and Foschini. In this paper, an minimum mean square error (MMSE) decoding algorithm without matrix inversion is proposed, by which the computational complexity can be reduced directly but the decoding performance is not affected. 展开更多
关键词 quasi-orthogonal space-time block coding (QSTBC) multiple input multiple output (MIMO) channel minimum mean square error (MMSE) decoding algorithm
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PERFORMANCE OF CLOSED LOOP TRANSMIT DIVERSITY IN A RAYLEIGH FADING CHANNEL
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作者 Yang Xin You Xiaohu 《Journal of Electronics(China)》 2006年第1期29-34,共6页
In this paper, the closed loop transmit diversity technology for the Wideband Code Division Multiple Access(WCDMA) systems is investigated in a multipath Rayleigh fading channel. The RAKE receiver model and the weighi... In this paper, the closed loop transmit diversity technology for the Wideband Code Division Multiple Access(WCDMA) systems is investigated in a multipath Rayleigh fading channel. The RAKE receiver model and the weighing vector algorithm are presented. The performance is theoretically analyzed in terms of the average maximal Signal-to-Noise Ratio(SNR) gain available over the Space-Time block coding based Transmit Diversity(STTD) technology. Theoretic analysis and simulation results show that the closed loop transmit diversity can provide a 3dB performance gain over the open loop scheme in a single path fading channel, while the performance gain decreases dramatically with the increasing inherent multipath diversity of the wireless channel. 展开更多
关键词 Wideband code Division multiple Access(WCDMA) Transmit diversity Closed loop Openloop space-time coding
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THE THEORETICAL BER PERFORMANCE ANALYSIS OF A COOPERATIVE DIVERSITY SCHEME IN FREQUENCY SELECTIVE FADING CHANNEL
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作者 Zhao Xianjing Zheng Baoyu 《Journal of Electronics(China)》 2007年第6期740-747,共8页
A novel cooperative diversity scheme based on Distributed Space-Time Block Coding and Multi-Carrier Code Division Multiple Access (DSTBC-MC-CDMA) is proposed which works well in frequency selective fading channels wit... A novel cooperative diversity scheme based on Distributed Space-Time Block Coding and Multi-Carrier Code Division Multiple Access (DSTBC-MC-CDMA) is proposed which works well in frequency selective fading channels with multiple single-antenna users. And an analytical error model is established to describe the symbol decoding errors between interusers, based on which a close form expression for theoretical Bit Error Rate (BER) performance of the scheme is derived to analyze the influence of the interuser decoding errors on the BER performance of the scheme. Then simulation is complimented to verify the analytic result above, which also shows that the BER performance of DSTBC-MC-CDMA outgoes that of non-cooperative MC-CDMA with considerable gains. Further- more, the simulations coincide with the theoretical results well. 展开更多
关键词 Cooperative diversity Theoretical Bit Error Rate (BER) Distributed space-time Block Coding (DSTBC) Multi-Carrier code Division multiple Access (MC-CDMA) Frequency selective fading channel
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